By 15 years of education, what he means is, after junior college (10+2), he has 3 years of an undergraduate degree (like B.Com) unlike an Engineering undergraduate degree (B.E.) which is of 4 years duration in India.
Dude, what all the universities say is that they need a 4 year undergraduate (UG) degree in US or its equivalent. By 'equivalent', it depends on school to school who accept the 15 year Indian UG degree. (Though they should as per the Bolognia accord. But not all schools are party to the accord, hence the difference).
Most of the Top B-schools do accept the 15 year Indian degree (some reserve it to be on a case to case basis), some explicitly saying so. Examples of schools accepting the 3 year UG degree: NYU - Stern, Dartmouth College - Tuck, Carnegie Mellon - Tepper, Univ of Rochester - Simon, Columbia Business School, Univ of Chicago GSB, Duke Fuqua and the HBS, Wharton et al.
Nevertheless, there are many schools which do not accept the 3 year UG degree and insist students having such degrees to either complete a masters degree or atleast an additional year of masters degree to make it equivalent to the US 4 year UG degree. Examples of school NOT accepting the 3 year Indian UG degree: UCLA Anderson, UC Berkely - Haas, Univ of Georgia - Terry, Georgetown univ - McDonough, Rice University - Jones etc.
Outside the US, most of the B-schools do accept the 3 year UG degree (Melbourne Business School, ISB

etc) with exceptions to the schools in Canada (Ivey, Rotman, Sauder etc)
In short, you will need to check with the individual school regarding your eligibility before you apply.
All the Best!!